Pressure-sensitive adhesives (PSA) are well known and are used for a variety of industrial, consumer and medical applications. Pressure-sensitive adhesives are characterized as being normally tacky and exhibiting instant tack when applied to a substrate. A variety of polymers have been used to manufacture PSA, for example, acrylic and methacrylic ester homo- or copolymers, butyl rubber-based systems, silicones, urethanes, vinyl esters and amides, olefin copolymer materials, natural or synthetic rubbers, and the like.
Flexible polymeric film materials are also known such as described in European Patent Applications Nos. 0107915 and 0147119 and PCT/GB91/00496 all of which being incorporated herein by reference to disclose materials with particular moisture vapor transmission rates which might be used as backing materials in connection with the present invention. Film materials which have moisture vapor transmission rates generally compatible with human skin are most preferred.
S. C. Temin, in the Encyclopedia of Polymer Science and Engineering, vol. 13 (New York: John Wiley & Sons, 1988), at pp. 345-368, and the Handbook of Pressure-sensitive Adhesive Technology, ed. Donates Satas (New York: Van Nostrand Reinhold Co., Inc., 1982), both provide a comprehensive overview of medical and other adhesives. A. H. Landrock, Adhesives Technology Handbook (Park Ridge, N.J.: Noyes Publications, 1985), pp. 154-156, and T. Flanagan, "Hot-melt Adhesives" in the Handbook of Adhesive Bonding, ed. C. V. Cagle (New York: McGraw-Hill, 1982), at pp. 8-1 to 8-17, describe hot-melt adhesives, i.e., adhesives which are applied to a substrate as a melt and which solidify and bond upon cooling. In contrast to the adhesive compositions of the present invention, hot-melt adhesives involve flowable polymers and do not allow for reversible adhesion.
U.S. Pat. No. 3,635,754 to Beede describes a temporary pressure-sensitive polyolefin-based adhesive product which is activated by heating at least 15.degree. C. above its melting point, and which, after cooling, remains tacky for an extended period of time.
U.S. Pat. No. 3,284,423 to Knapp describes a pressure-sensitive, cross-linked adhesive copolymer which is claimed to be storage stable in solution but readily cured when coated and heated. The copolymer consists of acrylic acid esters, lower alkyl acrylates (1-8 carbons, preferably 1-4 carbons), acrylic acid and glycidyl acrylate or methacrylate.
U.S. Pat. No. 3,535,195 to Davis et al. describes a pressure-sensitive, amine-containing adhesive which is stated to exhibit good tack yet be easily removable from a substrate.
U.S. Pat. No. 3,690,937 to Guse et al. relates to pressure-sensitive adhesives formulated from di-alkyl fumarates.
U.S. Pat. No. 3,838,079 to Kosaka et al. describes copolymer resins prepared from alkyl acrylates (1-20C) and maleic anhydride.
U.S. Pat. No. 3,299,010 to Samour describes a variety of adhesive compositions, some of which contain C-12 to C-24 residues. The patent teaches that the higher alkyl residues must be branched in order to avoid crystallinity. Some of the compositions contain acrylamido or other polar groups, and claims of adhesion to moist skin are made.
U.K. Patent No. 870,022, inventors Dahlquist and Zenk, teaches the use of a copolymer of octadecyl acrylate, acrylonitrile, ethyl acrylate, and acrylic acid as a low adhesion backsize on a pressure-sensitive adhesive tape.
PCT Publication No. W084/03837 teaches the use of copolymers which contain a polyalkylene oxide monomer in addition to acrylate. The polyoxyalkylene moiety is stated to impart hydrophilic behavior to the adhesive composition, thus facilitating adhesion to moist skin.
European Patent Application Publication No. 062682 describes the use of the monomer dodecyl methacrylate in a copolymer employed as an adhesive carrier for nitroglycerine. Small amounts of other comonomers (acrylic acid and short chain acrylates) are added to the reaction mixture to improve the properties of the copolymer.
The following references relate to side-chain crystallizable polymers: J. Polymer Sci.: Macromoleculer Review 8:117 (1974) and J. Polymer Sci.: Polymer Chemistry Edition 19:1871-1873 (1981).
A PCT publication, W091/14462, published October 3, 1991 refers to medical devices comprised of a substrate with a particular moisture vapor transmission rate with an adhesive thereon which is tacky at skin temperature but less tacky or not tacky at room temperature. A similar medical adhesive device is disclosed in W091/14461. The disclosure of both of these PCT publications is incorporated herein by reference to the extent they disclose such devices including particular backing layers, adhesives and methods of use and manufacture.